Organic light-emitting transistors with a thin metal layer covering a diffraction grating

ABSTRACT

We fabricated organic light-emitting transistors (OLETs) characterized by an Ag layer deposited on a one-dimensional (1D) or two-dimensional (2D) diffraction grating that acts as a combined gate insulator with SiO₂. The Ag layer was entirely covered with an organic crystal. Upon photoexcitation that crystal showed narrow linewidth emissions (NLEs) parallel to the substrate plane. The narrowed lines were either redshifted or blueshifted with rotation of the crystal around a normal to its surface with respect to the grating wave vector. Strong emissions (∼10⁴–10⁶ cd m⁻²) accompanied by current-injected NLEs were observed from the 1D and 2D grating OLETs.

KEYWORDS:

• Organic light-emitting transistors
• thiophene/phenylene co-oligomer
• diffraction gratings
• organic crystals

Acknowledgments

This work was supported by Grants-in-Aid for Scientific Research A (Grant No. 25248045) and C (Grant No. 23550208) and Challenging Exploratory Research (Grant No. 24655173) from Japan Society for the Promotion of Science (JSPS). The authors thank SCIVAX Corporation for preparing the 2D gratings on the substrate.